Re: "Smart" quotes

["Mark E. Shoulson" <mark@kli.org>]

On 05/26/2012 02:48 AM, Nicolas Goaziou wrote:
> Hello,
>
> "Mark E. Shoulson"<mark@kli.org>  writes:
>
>>> The regexp may be able to tell level 1 from level 2 quotes.
>> Do you mean that the author would use the same characters for both
>> first and second level quotes, and the regexp would be smart enough to
>> distinguish which level each was at?  I don't think that's possible,
>> and you probably don't either.
> Actually, I do. Since you can tell an opening quote from a closing one
> by the position of the white space (or parenthesis, beginning/end of
> line) near it, I think you can deduce the quote level. I may be wrong,
> though.

Maybe, if it's all on one line.  But if the quote is several lines long, 
can you sensibly count the levels?  I guess it doesn't actually matter, 
but it starts to get weird if you find yourself looking arbitrarily far 
back, and then you start building in exceptions for crossing paragraph 
boundaries... And then there's the fact that multi-paragraph quotes 
usually have an open-quote for each paragraph but only one close-quote 
at the end... Actually keeping count of what level you're at, 
accurately, is a classic example of a non-regular language; you need a 
push-down automaton to keep count, and regular expressions don't cut 
it.  Then again, Emacs regexps are more powerful than simple regular 
expressions, and we only would want to keep track of even vs odd level 
anyway.

I'm rambling.  In sum, I'm going to start off /not/ trying to solve that 
problem, and assume the writer is going to use alternating " and ' as 
typography requires and not try to second-guess what level we're at.  As 
that progresses, maybe I'll come to understand better what can and can't 
(and should and shouldn't) be deduced by the regexps.

>> "this is a 'quote', and that's all you need to know."
>>
>> becoming, for instance
>>
>> «this is a ‹quote›, and that’s all you need to know.»
> "this is a "quote", and that's all you need to know" is as parsable to
> me.
>
> As a side note, at least in French, many typographers would recommend
> "this is a /quote/, and that's all you need to know" here. Oh, and
> I know that was just an example.

I see; because I can tell that the second " must be an open-quote and 
not closing the first, due to its position relative to the spaces.  It 
does seem possible, but I think I'm going to try not solving that 
problem first.

(And French typography raises other problems, since French puts lots of 
space around the quote-marks, to the extent that French typists typing 
plain-text will often put a space on both sides of a quote-mark, making 
it hard to see whether it opens or closes... another issue, not 
necessarily solvable, to watch for.)

~mark